1. Field of the Invention
This invention relates to an improved mole chaser and particularly to a mole chaser that has an eccentric rotational vibration means to generate audio vibration and additional vibration by the eccetrically rotating impact member to create better effect to expel moles and other rodent animals.
2. Description of the Prior Art
Conventional mole chasers generally employ electronic or mechanical means to generate audio vibration to chase moles away. FIG. 1 illustrates one of such examples disclosed in U.S. Pat. No. 5, 822,917.
It includes a main stem A, a rotation vibrating means B, a cap C, a battery chamber D and a control circuit E.
In front of the battery chamber D, there is a separating wall J set between an impact member F and an open slot I. The impact member F is a substantially hollow tube with a plural number of convex bulges H formed in the inside wall and with the separating wall J at the bottom. The separating wall J has a spindle opening K in the center and a pair of spaced apertures L located on two opposite sides of the spindle opening K. A motor M is fixed to the separating wall L by means of a pair of screws R through the apertures L. The motor M has a spindle Q running through the spindle opening K. Therefore the motor M is located in the open slot I on one side of the separating wall J while the spindle Q is located on another side of the separating wall J.
The rotation vibration means B includes the motor M, a rotation block N fixedly attached to the motor spindle Q, a pair of doughnut-shaped rings B and a pair of pins G for holding the rings D in two spaced second slots S of the rotation block N. Each ring P has a center opening U which has a large diameter than the outside diameter of the pin G. Each pin G is held firmly on the rotation block N through a pair of apertures T. When the control circuit E activates the motor M, the motor spindle Q and the rotation block N will be rotated. The rings P held in the second slots S will be moved outward because of centrifugal force, and thus hitting the convex bulges H and generating audio vibration. As the ring P is doughnut-shaped and curved, and is moved outward by centrifugal force, the ring P will bounce back once hitting the convex bulges H. Therefore both the rings P and the bulges H will not be damaged. The service life of the rings P and the bulges H thus will not be negatively impacted. A strong vibration and audio frequency will be generated through the main stem A.
Since the motor M rotates at a constant speed, the audio frequency generated by rotating rings P hitting the bulges H is relatively constant and has little variation. The ensuing mole chasing effect is thus limited.